Quantification of Cardiotonic Steroids Potentially Regulated by Paraoxonase 3 in a Rat Model of Chronic Kidney Disease Using UHPLC-Orbitrap-MS
Abstract
Endogenous cardiotonic steroids (CTSs), such as telocinobufagin (TCB) and marinobufagin (MBG) contain a lactone moiety critical to their binding and signaling through the Na+/K+-ATPase. Their concentrations elevate in response to sodium intake and under volume-expanded conditions. Paraoxonase 3 (PON3) is an enzyme that can hydrolyze lactone substrates. Here, we examine the role of PON3 in regulating CTS levels in a rat model of chronic kidney diseases (CKD). TCB and MBG were extracted from rat urine samples, and the analyses were carried out using ultra-high pressure liquid chromatography–Orbitrap-mass spectrometry (UHPLC-Orbitrap-MS). Ten-week-old Dahl salt-sensitive wild type (SS-WT) and Dahl salt-sensitive PON3 knockout (SS-PON3 KO) rats were maintained on a high-salt diet (8% NaCl) for 8 weeks to initiate salt-sensitive hypertensive renal disease characteristic of this model. CTS extraction recovery from urine >80% was achieved. For animals maintained on a normal chow diet, the baseline amount of TCB excreted in 24 h urine of SS-PON3 KO rats (6.08 ± 1.47 ng/24 h; or 15.09 ± 3.25 pmol) was significantly higher than for SS-WT rats (1.48 ± 0.69 ng/24 h; or 3.67 ± 1.54 pmol, p 0.05) rats. These findings suggest that the presence and absence of PON3 dramatically affect the level of endogenous CTSs, indicating its potential role in CTS regulation.
Document Details
- Document Type
- Pub Defense Publication
- Publication Date
- Nov 05, 2022
- Source ID
- 10.3390/ijms232113565
Entities
People
- Chrysan J. Mohammed
- David J Kennedy
- Dragan Isailović
- Sabitri Lamichhane
- Steven T. Haller
Organizations
- Air Force Office of Scientific Research
- National Institutes of Health
- University of Toledo